Yes, the sample is showing just on local subnet and the vlan interface on the SRX. This could also be multiple interfaces as your note.
But you can have the vlan side of the OSPF setup on the switch. But naturally the SRX has to neighbor with the switch to get those routes to be learned on the SRX.
In shout you can consider the tunnel interface neighbors as if they were just two routers on your standard OSPF setup. And thne arrange the rest of the area configuration as you would if that link were a normal point to point OSPF link. Just forget about it being over an IPSEC tunnel.